Comparing: KV-13 vs. T-44-122

Development was started in the fall of 1941, under the initiative of Semyon Ginsburg. After successful trials in the fall of 1942, the development of a second prototype was begun.

Development of the vehicle started in 1943. The prototype was built by the end of the year and underwent trials in January 1944. In February 1944, the tank was re-equipped with a 122-mm gun and sent again for trials. Compared to the production vehicle, the 1943 prototype featured a different hull shape, turret, engine, and armor layout.